Evaporator for refrigerating machines



NOV. 10, 1936. D NEWMAN EVAPORATOR FOR REFRIGERATING MACHINES Filed Jan.26, 1935 Inventor: Delbert FT Newman,

Attorney"- Patented Nov. 10, 1936 I 7 I 2,060,633

UNITED STATES PA E T F C =v Delbert F. Newman, Schenectady, N. Y.,assignor to General Electric 'Company, a corporation of New Yorkapplication January 26, 1935, Serial No; 3,651 21 Claims. (ores-126) Myinvention relates to evaporators for reof the motor and compreS W thevap frigerating machines, rator is sufliciently cooled the operation ofthe An object ofmy invention is to provide an imr, a d Co p is stopped,t pp y provedevaporator of simple and rugged construcof liquidrefrigerant s Th liquid wit n i n and having a highly eflicientarrangement the evaporator continues to evaporate and absorb 5 forcirculating liquid refrigerant therein, heat from the chamber ll untilthe'temperature Another object of my invention i to provide a, of theevaporator rises to a predetermined value flooded evaporator forrefrigerating machines when the motor is a ain rt This cycle is havingan arrangement for producing circulation fientimleus and maintains tevaporator Within of refrigerant to assist the natural thermally in-Dredetermihed'range of p tu e 10 duced circulation in the evaporator ineither di- During e op t n of the refrigerating arection thereof. chineit is desirable to provide a continuous cir- Further objects andadvantages of my i culation of liquid refrigerant in the evaporator intion willvbecome apparent as th following order to obtain the highestpossible rate of heat 1o scription proceeds, and the features of noveltyabsorptionliquid refrigerant supp i d to which characterize my-inventionwill be pointed the evaporator may be utilized to p l e Ciriout withparticularity in the claims annexed to cu of refrigerant h evaporatorwhile and forming a part of this specification. t e liquid is beingsupplied theretohen l quid For. a better understanding of my inventionis not being supplied thereto a circulation of reference may be had tothe accompanying drawfrigerantwill be Produced y Slight te p rature .20.m in which Fig 1 shows a househoid refrigerdifferences, and it isdesirable that when the re-F ator provided with an evaporatorembodying'my frigerant s pp to the v porator is utilized invention, andFig. 2 is an enlarged perspective to induce a circulation of refrigeranttherein, this view partly in section of the evaporator ho n icirculation will be in the same direction as that A Fig. 1. v which isthermally induced. 2

Referring now to Fig. 1, I have shown 9, hou In accordance with myinvention I construct hold refrigerating machine provided with a cabithevap r w t a he d headers and net l0 having a food compartment II whichis a plurality of depending refrigerant circulatin cooled by anevaporator l2 arranged therein and Passages tu s and provide a manifoldfor psupplied with refrigerant from a motor and complying ant t t evapoat r a d a a d so pressor unit contained in a casing l3 mounted on I onject refrigerant inte the P a in a the top of the cabinet I0. A door I4 is provided to e Whieh p odu a circulation assisting the close thecompartment II whenthe refrigerator natural rmal cir t of the q d i isbeing used. During the operation f th r erant in theevaporator in eitherdirection therefrigerating machine shown, gaseous refrigerant 01' a v iscompressed within the casing in and flows into efe i to Fi u e 2, t eevap at r 1 coma conduit i5 formed in Shell is a d comprising prisesinner and outer metal sheets 23-and 24 a condenser. The gaseousrefrigerant isair respectively secured together about their edges,cooled by natural draft and liquefiedin the eonthe sheet 23 being bentover the edge of the sheet 40 denser and flows through a connection H toa, 24 as indicated at 25. The headers 20 and-2| are 40 receiver or floatvalve, chamber la, The liquid formed by indentations in the sheets nearthe flows in regulated quantities from the chamber opposite endsthereof, the sheets being bent in a it through a conduit H to theevaporator I 2. U-shap'ed form with the headers at the upper Theabsorption of heat from the chamber ll vaends of the U. Depending fromthe headers 20 porizesv the liquid refrigerant within the evapoand 2|respectivelyare a plurality of separate rator and the vapor collects inheaders '20 and U-shaped refrigerant passages or conduits 26 and 2|, andis withdrawn through conduit 22 by op- \2\l1 respectively. TheseU-shaped passages are eration of the-compressor, and returned to theormed by p v corrugations or indenta- 7 casing IS. The motor andcompressor within the ons in the outer sheet 24 of the evaporator, partocasing B are operated intermittently'under the ly in the sides andpartly in the bottom of the control of a thermostat in accordance withthe evaporator. The lower portions of the passages temperature of theevaporator so as to maintain are available for cooling the bottom of theevapthe desired temperature in the cabinet. I Liquid, orator, andfreezing trays or similar articles which refrigerant is supplied to theevaporator by opmay be supported thereon. The passages 26 are eration ofthe float valve at I 8 duringoperation connected as a group with bothends of each 55 passage opening into the header below the level ofliquid refrigerant therein and connected in substantially longitudinalalinement along said header with the ends of the other passages 26. Thepassages 21 are connected to the header 2| in a similar manner. Liquidrefrigerant will circulate from one end of each of the passages 26 and21 to the other end thereof, the direction being determined by thermalconditions in each particular passage. In order to utilize'the liquidrefrigerant supplied to the evaporator to induce a circulation ofrefrigerant in the direction of the natural thermal circulation in eachof the passages in either direction, I provide a U-shapedmanifold 28 inthe bottom of the evaporator between the ends of the tubes 26 and 2! andcommunicating with the lower ends of the U-shaped passages 28 and 21through ducts 29 and 30, respectively.

' The refrigerant from the manifold 28 is injected directly into thepassages 26 and 21 transversely of the flow therein and will flow in thesame direction as the refrigerant circulating in the passages. Thedirection of flow is determined by the natural thermal circulationtherein, for any bubbles of gaseous refrigerant entering the passagesthrough the ducts 29 and 30 will be carried by the circulation in thedirection thereof and when rising will assist the circulation. It isthus evident that regardless of the direction of the thermally inducedcirculation in the passages, the injection of refrigerant into thesepassages from the manifold 28 will assist the thermally inducedcirculation. In order to maintain the same level of liquid in theheaders 20 and 2| and to provide a passage for liquid and gaseousrefrigerant between the headers, I provide a horizontal conduit 3|connecting the headers and arranged so that the normal level of liquidrefrigerant indicated at 32 lies within the conduit. Gaseous refrigerantis withdrawn from the evaporator through the conduit 22 connected to theheader 2|.

During the idle periods when the compressor of the refrigerating machineis not operating refrigerant will circulate in the depending U- shapedpassages in directions determined by the thermally induced currents ineach passage. When the motor and compressor unit is started liquidrefrigerant will be injected into the passages 26 and 21 through ducts29 and 30 respectively. Some of the liquid will vaporize and the liquidand vapor will induce a circulation assisting the natural thermalcirculation in each of the passages. The rapid circulation produced bythis injection of refrigerant will make possible a higher rate of heatabsorption, thus ice trays or articles of. food placed on the evaporatoror within the refrigerator will be cooled rapidly.

The evaporator embodying my invention is of simple construction, iseasily manufactured and provides a highly efficient arrangement forcirculating refrigerant.

While I have shown and described my invention in connection with ahousehold refrigerating machine, other applications will readily beapparent to those skilled in the art. I do not, therefore, desire myinvention to be limited to the particular construction shown anddescribed, and I intend in the appended claims to cover allmodifications within the spirit and scope of my invention.

Letters Patent of the United States,.is: J

1. A flooded evaporator for refrigerating machines comprising a headerand a depending U- shaped refrigerant circulating passage, meanscommunicating with the lower portion of said U- shaped passage forinjecting liquid refrigerant into said U-shaped passage and forassisting the thermally induced circulation of refrigerant in saidpassage in either direction of said thermally induced circulation, andmeans for withdrawing gaseou refrigerant from said header.

2. A flooded evaporator for refrigerating Inachines comprising a headerand a depending U- shaped refrigerant circulating passage, meanscommunicating with the mid-portion of said U- shaped passage forinjecting liquid refrigerant into said U-shaped passage and forassisting the thermally induced circulation of refrigerant in saidpassage in either direction of said thermally induced circulation, andmeans for withdrawing gaseous refrigerant from said header.

3. A flooded evaporator for refrigerating machines comprising a. headerand a plurality of depending U-shaped refrigerant circulating passages,means communicating with the lower portion of each of said U-shapedpassages for injecting liquid refrigerant into said U-shaped passagesand for assisting the thermally induced circulation of refrigerant insaid U-shaped passages in either direction of said thermally inducedcirculation, and means for withdrawing gaseous refrigerant from saidheader.

4. A flooded evaporator for refrigerating machines comprising a headerand a plurality of separate depending U-shaped refrigerant circulatingpassages, means communicating with the lower portion of each of saidU-shaped passages for injecting liquid refrigerant into said U-shapedpassages and for assisting the thermally induced circulation ofrefrigerant in said U-shaped passages in either direction of saidthermally induced circulation, and means for withdrawing gaseousrefrigerant from said header.

5. A flooded evaporator for refrigerating machines comprising a headerand a plurality of separate depending U-shaped refrigerant circulatingpassages, both of the ends of each of said passages communicating withsaid header and all of the ends of said passages being substantially inlongitudinal alinement along saidheader, means communicating with thelower portion of each of said U-shaped passages for injecting liquidrefrigerant into said U-shaped passages, and means for withdrawinggaseous refrigerant from said header.

6. A flooded evaporator for refrigerating machines comprising a headerand a plurality of depending U-shaped refrigerant circulating passages,both of the ends of each of said passages communicating with said headerand all of the ends of said passages being substantially in longitudinalalinement along said header, means communicating with the lower portionof each of said U-shaped passages for injecting liquid refrigerant intosaid U-shaped passages and for inducing a circulation of refrigerantthrough said passages, and means for withdrawing refrigerant from saidheader.

'7. A flooded evaporator for refrigerating machines comprising a headerand a plurality of separate depending U-shaped refrigerant circulatingpassages, both of the ends of each of said passages communicating withsaid header and all of the ends of said passages being substantiallyWhat I claim as new and desire to secure by -.in'-l0n itudinal alinementa n id r,

means communicating with the lower portion of each of said U-shapedpassages for injecting liquid refrigerant into said U-shaped passagesand for inducing a circulation of refrigerant through said passages, andmeans for withdrawing refrigerant from said header.

' 8. A flooded evaporator for refrigerating machines comprising a headerand a; plurality of depending U-shaped refrigerant circulating passages,both of the ends of each of said U-shaped passages communicating withsaid header and all of the ends of said U-shaped'passages beingsubstantially in longitudinal alinement along said header, saidevaporator having a portion arranged to support freezing trays orthe'like in heat exchange relation with refrigerant in said passages,means communicating with the midportion of each of saidU-shaped passagesfor injecting liquid refrigerant into said U-shaped passages and forinducing a circulation of refrigerant through said passages, and meansfor withdrawing gaseous refrigerant from said header.

'9. A flooded evaporator for refrigerating machines comprising a header,and a plurality of separate depending U-shaped refrigerant circulat'ingpassages, both of theends of each of said withdrawing gaseous U-shapedpassages communicating with said header and all of the ends of saidU-shaped pas sages being substantially in longitudinal alinement alongsaid header, said evaporator having a portion arranged to supportfreezing trays or the like in heat exchange relation with refrigerant insaid passages, means communicating with the mid-portion of each of saidU-shaped passages for injecting liquid refrigerant into said U-shapedpassages and for inducing a circulation of refrigerant through saidpassages, and means for refrigerant from said header.v

10. A flooded evaporator for refrigerating.machines comprising a headerand a plurality of separate depending U-shaped refrigerant circulatingpassages, both of the ends of each of said U-shaped passages.communicating with said header and all of the ends of said U-shapedpassages being substantially in longitudinal alinement along saidheader, said evaporator having a portion arranged to support freezingtrays or the like in heat exchange relation with refrigerant in saidpassages, means including a plurality of ducts, one communicating withthe mid-portion of each of said U-shaped passages for admitting liquidrefrigerant to said evaporator and for inducing a circulationofrefrigerant through said passages, and means for withdrawing gaseousrefrigerant from said header.

11. A flooded evaporator for refrigerating machines comprising twoheaders,,a plurality of depending U-shaped refrigerant circulatingpassages arranged in two groups, all of the U-shaped uid refrigerantthrough said passages, and means for withdrawing gaseous refrigerantfrom said headers.

12. A flooded evaporator for refrigerating machines comprising twoheaders, a plurality of separate depending U-shaped refrigerantcirculating passages arranged in two groups, all of the U shapedpassages of one of said groups communieating with one of saidheaders'and being arranged substantially in longitudinal alinement alongsaid header, all of the passages of the other of said groupscommunicating with the other of said. headers and being arrangedsubstantially in longitudinal alinement along the other of said catingwith one of said headers and being arranged substantially inlongitudinal alinement along saidheader, all of the passages of theother of said groups communicating with the other of said headers andbeing arranged substantially in longitudinal alinement along the otherof said headers, means including a U-shaped manifold communicating withthe mid-portion of each of said passages for admitting liquidrefrigerant to said evaporator and for inducing a circulation of liquidrefrigerant through said passages, and means'for withdrawing gaseousrefrigerant from said headers. I v

14. A flooded evaporator for refrigerating machines comprising twoheaders, a plurality of depending U-shaped refrigerant circulatingpassages arranged in two groups, all of the U-shaped passages of one ofsaid groups communicating with one of said headers and being arrangedsubstantially in longitudinal alinement'along'said header, all ofthe'passages of the other of said groups communicating with the other ofsaid headers and being arranged substantially in longitudinal alinementalong the other of said headers, means including a plurality of ducts,one communicating with the mid-portion of each of shaped passages of oneof said groups communisaid passages for admitting liquid refrigerant to.

said evaporator and for inducing a circulation of liquid refrigerantthroligh said passages, and means for withdrawing gaseous refrigerantfrom said headers.

15. A fiooded'evaporator for refrigerating machines comprising twoheaders, a plurality of separate depending U-shaped refrigerantcirculating passages arranged in two groups, all of the U- shapedpassages of one of said groups communieating with one of said headersand being arranged substantially in longitudinal alinement along saidheader, all of the passages of the other of said groups communicatingwith the other of said headers and being arranged substantially inlongitudinal alinement along the other of said headers, meanscommunicating with the mid-portion of each of said passages foradmitting liquid refrigerant to said evaporator and for inducing acirculation of liquid refrigerant through said passages, means includinga connection between said headers for maintaining a common liquid leveltherein, and means for withdrawing gaseous refrigerant from said,

arranged substantially in longitudinal alinementalong said header, allof the passages of the other connection between said headers formaintaining a common liquid level therein, and means for withdrawinggaseous refrigerant from said headers.

17. A flooded evaporator for refrigerating machines comprising inner andouter sheet metal walls provided with indentations forming two .headersand a plurality of separate refrigerant circulating passages dependingfrom said headers, said passages comprising a plurality of U- shapedloops arranged in two groups, all of the loops of one of said groupscommunicating at both ends with one of said headers, all of the loopsof'the other of said groups communicating at both ends .with the otherof said headers, means formed between said inner and outer walls foradmitting liquid refrigerant to said evaporator, means communicatingwith each of said U-shaped passages for inducing a circulationofrefrigerant in said passages, and means for withdrawing gaseousrefrigerant from said headers.

18. A flooded evaporator for refrigerating machines comprising inner andouter sheet metal walls provided with indentations forming two headersand a plurality of refrigerant circulating passages depending from saidheaders, said passages comprising a plurality of U-shaped loops arrangedin two groups, all of the loops of one of said groups communicating atboth ends with one of said headers, all of the loops of the other ofsaid groups communicating at both ends with the other of said headers,means -including a manifold formed between said inner and outer wallsfor admitting liquid refrigerant to said evaporator, means includingducts connecting said manifold and each of said U-shaped passages forinducing a circulation of refrigerant in said passages, and means forwithdrawing gaseous refrigerant from said headers.

19. A flooded evaporator for refrigerating machines comprising inner andouter sheet metal walls provided with indentations forming two headersand a plurality of separate refrigerant circulating passages dependingfrom said headers, said passages comprising a plurality of U- shapedloops arranged in two groups, all of the loops of one of said groupscommunicating at both ends with one of said headers, all of the loops ofthe other of said groups communicating at both ends with the other ofsaid headers, means formed between said inner and outer walls foradmitting liquid refrigerant to said evaporator, means communicatingwith each of said U-shaped passages for inducing a circulation ofrefrigerant in said passages, means including a connection between saidheaders for maintaining a common-liquid level therein, and means forwithdrawing gaseous refrigerant from said headers.

20. A flooded evaporator for refrigerating machines comprising inner andouter sheet metal walls provided with indentations forming two headers,and a plurality of depending refrigerant circulating passages, saidpassages comprising a plurality of U-shaped loops arranged in twogroups, all the loops of one of said groups communicating at both endswith one of said headers, all theloops of the other of said groupscommunicatingat both ends with the other of said headers, meansincluding a manifold formed between said inner and outer walls foradmitting liquid refrigerant to said evaporator, means including ductsconnecting said manifold and each of said U-shaped passages for inducinga circulation of refrigerant in said passages, means including aconduit'connecting said headers for maintaining a common level of liquidrefrigerant therein, and means for withdrawing gaseous refrigerant fromsaid headers.

21. A flooded evaporator for refrigerating machines comprising inner andouter sheet metal walls provided with indentations forming two headersand a plurality of depending refrigerant circulating passages, saidpassages comprising a plurality of U-shaped loops arranged in twogroups, all the loops of one of said groups communicating at both endswith one of said headers, all the loops of the other of said groupscommunicating at both ends with the other of said headers, meansincluding a manifold formed said headers.

' DELBERT F. NEWMAN.

